When you know both yourself as well as your competition, you are never in danger. To know yourself and not others, gives you half a chance of winning. Knowing neither yourself or your competition puts you in a position to lose.
Sun TzuIf our soldiers are not overburdened with money, it is not because they have a distaste for riches; if their lives are not unduly long, it is not because they are disinclined to longevity.
Sun TzuAll warfare is based on deception. Therefore, when capable, feign incapacity; when active, inactivity. When near, make it appear that you are far away; when far away, that you are to lure him; feign disorder and strike him. When he concentrates, prepare against him; where he is strong, avoid him. Anger his general and confuse him. Pretend inferiority and encourage his arrogance.
Sun TzuYou can ensure the success of your attacks if you only attack places that are undefended. You can ensure the safety of your defense if you only hold positions that cannot be attacked. Therefore, that general is skillful in attack whose opponent does not know what to defend; and he is skillful in defense whose opponent does not know what to attack.
Sun Tzu